Electrochromic materials undergo a reversible change of color due to their oxidation or reduction. Devices incorporating these materials have been utilized in the construction of mirrors, displays, and windows for example. Nanoparticle based films can be useful in many electrochemical applications, examples of which include electrochromic devices, batteries, and solar cells. It is often desirable, given the final application of the device, for an electrochromic device to be optically transparent. Methods of producing optically transparent electrochromic devices and articles are therefore also desirable.